pypa/pip · error · PEP723Exception

Multiple {name!r} blocks found in {scriptfile!r}

Error message

Multiple {name!r} blocks found in {scriptfile!r}

What it means

Raised by pep723_metadata() when a Python script contains more than one PEP 723 `# /// script` metadata block. PEP 723 (inline script metadata) allows exactly one such block per script; the regex at pep723.py:6 finds multiple matching blocks of type 'script' and pip refuses to guess which one applies.

Source

Thrown at src/pip/_internal/req/pep723.py:26

class PEP723Exception(ValueError):
    """Raised to indicate a problem when parsing PEP 723 metadata from a script"""

    def __init__(self, msg: str) -> None:
        self.msg = msg


def pep723_metadata(scriptfile: str) -> dict[str, Any]:
    with open(scriptfile, encoding="utf8") as f:
        script = f.read()

    name = "script"
    matches = list(
        filter(lambda m: m.group("type") == name, re.finditer(REGEX, script))
    )

    if len(matches) > 1:
        raise PEP723Exception(f"Multiple {name!r} blocks found in {scriptfile!r}")
    elif len(matches) == 1:
        content = "".join(
            line[2:] if line.startswith("# ") else line[1:]
            for line in matches[0].group("content").splitlines(keepends=True)
        )
        try:
            metadata = tomllib.loads(content)
        except Exception as exc:
            raise PEP723Exception(f"Failed to parse TOML in {scriptfile!r}") from exc
    else:
        raise PEP723Exception(
            f"File does not contain {name!r} metadata: {scriptfile!r}"
        )

    return metadata

View on GitHub (pinned to d7d0d0a394)

Solutions

1. Open the script and delete all but one `# /// script` ... `# ///` block, keeping the one with the correct dependencies.
2. Merge the dependencies from the duplicate blocks into a single block if both are needed.
3. Re-run `pip run <script>` (or the consuming command) to confirm only one block remains.

Example fix

# before (two blocks)
# /// script
# dependencies = ["requests"]
# ///
# /// script
# dependencies = ["rich"]
# ///
# after (merged)
# /// script
# dependencies = ["requests", "rich"]
# ///

import re

PEP723_RE = r"(?m)^# /// (?P<type>[a-zA-Z0-9-]+)$\s(?P<content>(^#(| .*)$\s)+)^# ///$"

def assert_single_script_block(scriptfile: str) -> None:
    with open(scriptfile, encoding="utf8") as f:
        script = f.read()
    matches = [m for m in re.finditer(PEP723_RE, script) if m.group("type") == "script"]
    if len(matches) > 1:
        raise ValueError(f"{scriptfile} has {len(matches)} PEP 723 script blocks; expected 1")

null

from pip._internal.req.pep723 import pep723_metadata, PEP723Exception

try:
    meta = pep723_metadata(scriptfile)
except PEP723Exception as e:
    if e.msg.startswith("Multiple"):
        # prompt user to dedupe blocks
        ...
    raise

When it happens

Trigger: A .py file passed to `pip run` (or PEP 723 processing) that has two `# /// script` ... `# ///` sections, e.g. from concatenating two scripts or a botched merge. The filter at pep723.py:21-23 yields len(matches) > 1.

Common situations: Merging two PEP 723 scripts without removing one block. A template/boilerplate tool injecting a second block. Copy-pasting a script that already had a block into another that also had one.

Related errors

• Failed to parse TOML in {scriptfile!r}
• File does not contain {name!r} metadata: {scriptfile!r}
• --requirements-from-script can only be given once
• <dynamic: PEP723 exception message (exc.msg)>
• [dependency-groups] resolution failed for '{groupname}' from

AI-assisted analysis of pypa/pip@d7d0d0a394 (2026-08-04). Data as JSON: /data/errors/5de8e2668b112dc7.json. Report an issue: GitHub.